1
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Ying QL, Nichols J. Relationship of PSC to embryos: Extending and refining capture of PSC lines from mammalian embryos. Bioessays 2024:e2400077. [PMID: 39400400 DOI: 10.1002/bies.202400077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2024] [Accepted: 09/07/2024] [Indexed: 10/15/2024]
Abstract
Pluripotent stem cell lines derived from preimplantation mouse embryos have opened opportunities for the study of early mammalian development and generation of genetically uncompromised material for differentiation into specific cell types. Murine embryonic stem cells are highly versatile and can be engineered and introduced into host embryos, transferred to recipient females, and gestated to investigate gene function at multiple levels as well as developmental mechanisms, including lineage segregation and cell competition. In this review, we summarize the biomedical motivation driving the incremental modification to culture regimes and analyses that have advanced stem cell research to its current state. Ongoing investigation into divergent mechanisms of early developmental processes adopted by other species, such as agriculturally beneficial mammals and birds, will continue to enrich knowledge and inform strategies for future in vitro models.
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Affiliation(s)
- Qi-Long Ying
- Eli and Edythe Broad CIRM Center for Regenerative Medicine and Stem Cell Research at USC, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - Jennifer Nichols
- MRC Human Genetics Unit, Institute for Genetics and Cancer, University of Edinburgh, Edinburgh, UK
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2
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Tan JP, Liu X, Polo JM. Reprogramming fibroblast into human iBlastoids. Nat Protoc 2024; 19:2298-2316. [PMID: 38632379 DOI: 10.1038/s41596-024-00984-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2023] [Accepted: 02/12/2024] [Indexed: 04/19/2024]
Abstract
The study of early human embryogenesis has relied on the use of blastocysts donated to research or simple stem cell culture systems such as pluripotent and trophoblast stem cells, which have been seminal in shedding light on many key developmental processes. However, simple culture systems lack the necessary complexity to adequately model the spatiotemporal, cellular and molecular dynamics occurring during the early phases of embryonic development. As such, an in vitro model of the human blastocyst is advantageous in many aspects to decipher human embryogenesis. Here we describe a step-by-step protocol for the generation of induced blastoids (iBlastoids), an in vitro integrated model of the human blastocyst derived via somatic reprogramming. This protocol details the workflow for reprogramming of human dermal fibroblasts and subsequent generation of iBlastoids using the reprogramming intermediates, which together takes ~27 days (21 days for reprogramming and 6 days for iBlastoid generation). We also discuss several characterization/functional assays that can be used on the iBlastoids. We believe that a person trained in cell culture with ~1 year of experience with human somatic cell and reprogramming/cell differentiation assays would be able to perform this protocol. In short, the iBlastoids present an alternative tool as a model to the blastocyst to facilitate the scientific community in the exploration of early human development.
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Affiliation(s)
- Jia Ping Tan
- Department of Anatomy and Developmental Biology, Monash University, Clayton, Victoria, Australia
- Development and Stem Cells Program, Monash Biomedicine Discovery Institute, Clayton, Victoria, Australia
- Australian Regenerative Medicine Institute, Monash University, Clayton, Victoria, Australia
| | - Xiaodong Liu
- School of Life Sciences, Westlake University, Hangzhou, Zhejiang, China.
- Research Center for Industries of the Future, Westlake University, Hangzhou, China.
- Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang, China.
- Westlake Institute for Advanced Study, Hangzhou, Zhejiang, China.
| | - Jose M Polo
- Department of Anatomy and Developmental Biology, Monash University, Clayton, Victoria, Australia.
- Development and Stem Cells Program, Monash Biomedicine Discovery Institute, Clayton, Victoria, Australia.
- Australian Regenerative Medicine Institute, Monash University, Clayton, Victoria, Australia.
- Adelaide Centre for Epigenetics, School of Biomedicine, Faculty of Health and Medical Sciences, The University of Adelaide, Adelaide, South Australia, Australia.
- The South Australian Immunogenomics Cancer Institute, Faculty of Health and Medical Sciences, The University of Adelaide, Adelaide, South Australia, Australia.
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3
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Linneberg-Agerholm M, Sell AC, Redó-Riveiro A, Perera M, Proks M, Knudsen TE, Barral A, Manzanares M, Brickman JM. The primitive endoderm supports lineage plasticity to enable regulative development. Cell 2024; 187:4010-4029.e16. [PMID: 38917790 PMCID: PMC11290322 DOI: 10.1016/j.cell.2024.05.051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Revised: 02/27/2024] [Accepted: 05/28/2024] [Indexed: 06/27/2024]
Abstract
Mammalian blastocyst formation involves the specification of the trophectoderm followed by the differentiation of the inner cell mass into embryonic epiblast and extra-embryonic primitive endoderm (PrE). During this time, the embryo maintains a window of plasticity and can redirect its cellular fate when challenged experimentally. In this context, we found that the PrE alone was sufficient to regenerate a complete blastocyst and continue post-implantation development. We identify an in vitro population similar to the early PrE in vivo that exhibits the same embryonic and extra-embryonic potency and can form complete stem cell-based embryo models, termed blastoids. Commitment in the PrE is suppressed by JAK/STAT signaling, collaborating with OCT4 and the sustained expression of a subset of pluripotency-related transcription factors that safeguard an enhancer landscape permissive for multi-lineage differentiation. Our observations support the notion that transcription factor persistence underlies plasticity in regulative development and highlight the importance of the PrE in perturbed development.
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Affiliation(s)
- Madeleine Linneberg-Agerholm
- Novo Nordisk Foundation Center for Stem Cell Medicine (reNEW), University of Copenhagen, 2200 Copenhagen N, Denmark
| | - Annika Charlotte Sell
- Novo Nordisk Foundation Center for Stem Cell Medicine (reNEW), University of Copenhagen, 2200 Copenhagen N, Denmark
| | - Alba Redó-Riveiro
- Novo Nordisk Foundation Center for Stem Cell Medicine (reNEW), University of Copenhagen, 2200 Copenhagen N, Denmark
| | - Marta Perera
- Novo Nordisk Foundation Center for Stem Cell Medicine (reNEW), University of Copenhagen, 2200 Copenhagen N, Denmark
| | - Martin Proks
- Novo Nordisk Foundation Center for Stem Cell Medicine (reNEW), University of Copenhagen, 2200 Copenhagen N, Denmark
| | - Teresa E Knudsen
- Novo Nordisk Foundation Center for Stem Cell Medicine (reNEW), University of Copenhagen, 2200 Copenhagen N, Denmark
| | - Antonio Barral
- Centro de Biología Molecular Severo Ochoa (CBM), CSIC-UAM, 28049 Madrid, Spain
| | - Miguel Manzanares
- Centro de Biología Molecular Severo Ochoa (CBM), CSIC-UAM, 28049 Madrid, Spain
| | - Joshua M Brickman
- Novo Nordisk Foundation Center for Stem Cell Medicine (reNEW), University of Copenhagen, 2200 Copenhagen N, Denmark.
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4
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Pennings G. IVF embryos in the bin, embryo-like structures in the spotlight. Reprod Biomed Online 2024; 48:103886. [PMID: 38614064 DOI: 10.1016/j.rbmo.2024.103886] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2023] [Revised: 02/05/2024] [Accepted: 02/06/2024] [Indexed: 04/15/2024]
Abstract
Embryo-like structures (ELS) are intended for the study of embryonic development without the use of human supernumerary embryos. Scientists working in countries that do not allow research on embryos hope that these structures will replace natural embryos. The interest in ELS is largely based on two misconceptions: the belief that there is a shortage of research embryos and the belief that research on ELS will make research on natural embryos redundant. This paper argues that research efforts should be refocused on natural embryos.
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Affiliation(s)
- Guido Pennings
- Bioethics Institute Ghent (BIG), Department of Philosophy and Moral Science, Ghent University, Ghent, Belgium..
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5
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Saadeldin IM, Ehab S, Noreldin AE, Swelum AAA, Bang S, Kim H, Yoon KY, Lee S, Cho J. Current strategies using 3D organoids to establish in vitro maternal-embryonic interaction. J Vet Sci 2024; 25:e40. [PMID: 38834510 PMCID: PMC11156602 DOI: 10.4142/jvs.24004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2024] [Revised: 03/14/2024] [Accepted: 03/28/2024] [Indexed: 06/06/2024] Open
Abstract
IMPORTANCE The creation of robust maternal-embryonic interactions and implantation models is important for comprehending the early stages of embryonic development and reproductive disorders. Traditional two-dimensional (2D) cell culture systems often fail to accurately mimic the highly complex in vivo conditions. The employment of three-dimensional (3D) organoids has emerged as a promising strategy to overcome these limitations in recent years. The advancements in the field of organoid technology have opened new avenues for studying the physiology and diseases affecting female reproductive tract. OBSERVATIONS This review summarizes the current strategies and advancements in the field of 3D organoids to establish maternal-embryonic interaction and implantation models for use in research and personalized medicine in assisted reproductive technology. The concepts of endometrial organoids, menstrual blood flow organoids, placental trophoblast organoids, stem cell-derived blastoids, and in vitro-generated embryo models are discussed in detail. We show the incorportaion of organoid systems and microfluidic technology to enhance tissue performance and precise management of the cellular surroundings. CONCLUSIONS AND RELEVANCE This review provides insights into the future direction of modeling maternal-embryonic interaction research and its combination with other powerful technologies to interfere with this dialogue either by promoting or hindering it for improving fertility or methods for contraception, respectively. The merging of organoid systems with microfluidics facilitates the creation of sophisticated and functional organoid models, enhancing insights into organ development, disease mechanisms, and personalized medical investigations.
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Affiliation(s)
- Islam Mohamed Saadeldin
- Comparative Medicine Department, King Faisal Specialist Hospital and Research Centre, Riyadh 11211, Saudi Arabia
| | - Seif Ehab
- Biomedical Sciences Program, University of Science and Technology, Zewail City of Science and Technology, Giza 11341, Egypt
| | - Ahmed Elsayed Noreldin
- Department of Histology and Cytology, Faculty of Veterinary Medicine, Damanhour University, the Scientific Campus, Damanhour 22511, Egypt
| | - Ayman Abdel-Aziz Swelum
- Department of Animal Production, College of Food and Agriculture Sciences, King Saud University, Riyadh 11451, Saudi Arabia
- Department of Theriogenology, Faculty of Veterinary Medicine, Zagazig University, Zagazig 44519, Egypt
| | - Seonggyu Bang
- College of Veterinary Medicine, Chungnam National University, Daejeon 34134, Korea
- College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul 08826, Korea
| | - Hyejin Kim
- Division in Biomedical Art, Department of Fine Art, Incheon Catholic University Graduate School, Incheon 21986, Korea
| | - Ki Young Yoon
- Department of Companion Animal, Shingu College, Seongnam 13174, Korea
| | - Sanghoon Lee
- College of Veterinary Medicine, Chungnam National University, Daejeon 34134, Korea
| | - Jongki Cho
- College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul 08826, Korea.
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6
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Sepulveda-Rincon LP, Wang YF, Whilding C, Moyon B, Ojarikre OA, Maciulyte V, Hamazaki N, Hayashi K, Turner JMA, Leitch HG. Determining the potency of primordial germ cells by injection into early mouse embryos. Dev Cell 2024; 59:695-704.e5. [PMID: 38359835 DOI: 10.1016/j.devcel.2024.01.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Revised: 11/29/2023] [Accepted: 01/24/2024] [Indexed: 02/17/2024]
Abstract
Primordial germ cells (PGCs) are the earliest precursors of the gametes. During normal development, PGCs only give rise to oocytes or spermatozoa. However, PGCs can acquire pluripotency in vitro by forming embryonic germ (EG) cells and in vivo during teratocarcinogenesis. Classic embryological experiments directly assessed the potency of PGCs by injection into the pre-implantation embryo. As no contribution to embryos or adult mice was observed, PGCs have been described as unipotent. Here, we demonstrate that PGCs injected into 8-cell embryos can initially survive, divide, and contribute to the developing inner cell mass. Apoptosis-deficient PGCs exhibit improved survival in isolated epiblasts and can form naive pluripotent embryonic stem cell lines. However, contribution to the post-implantation embryo is limited, with no functional incorporation observed. In contrast, PGC-like cells show an extensive contribution to mid-gestation chimeras. We thus propose that PGC formation in vivo establishes a latent form of pluripotency that restricts chimera contribution.
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Affiliation(s)
- Lessly P Sepulveda-Rincon
- Medical Research Council (MRC) Laboratory of Medical Sciences (LMS), London W12 0HS, UK; Institute of Clinical Sciences (ICS), Faculty of Medicine, Imperial College London, London W12 0HS, UK.
| | - Yi-Fang Wang
- Medical Research Council (MRC) Laboratory of Medical Sciences (LMS), London W12 0HS, UK
| | - Chad Whilding
- Medical Research Council (MRC) Laboratory of Medical Sciences (LMS), London W12 0HS, UK
| | - Benjamin Moyon
- Medical Research Council (MRC) Laboratory of Medical Sciences (LMS), London W12 0HS, UK
| | - Obah A Ojarikre
- Sex Chromosome Biology Laboratory, The Francis Crick Institute, London NW1 1AT, UK
| | - Valdone Maciulyte
- Sex Chromosome Biology Laboratory, The Francis Crick Institute, London NW1 1AT, UK
| | - Nobuhiko Hamazaki
- Department of Stem Cell Biology and Medicine, Graduate School of Medical Sciences, Kyushu University, Maidashi 3-1-1, Higashi-ku, Fukuoka 812-8582, Japan
| | - Katsuhiko Hayashi
- Department of Stem Cell Biology and Medicine, Graduate School of Medical Sciences, Kyushu University, Maidashi 3-1-1, Higashi-ku, Fukuoka 812-8582, Japan; Department of Genome Biology, Graduate School of Medicine, Osaka University, Yamadaoka 2-2, Suita 565-0871, Japan; Graduate School of Frontier Biosciences, Osaka University, Yamadaoka 2-2, Suita 565-0871, Japan; Premium Research Institute for Human Metaverse Medicine (WPI-PRIMe), Osaka University, Yamadaoka 2-2, Suita 565-0871, Japan
| | - James M A Turner
- Sex Chromosome Biology Laboratory, The Francis Crick Institute, London NW1 1AT, UK
| | - Harry G Leitch
- Medical Research Council (MRC) Laboratory of Medical Sciences (LMS), London W12 0HS, UK; Institute of Clinical Sciences (ICS), Faculty of Medicine, Imperial College London, London W12 0HS, UK.
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7
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Pereira Daoud AM, Dondorp WJ, Bredenoord AL, De Wert GMWR. Potentiality switches and epistemic uncertainty: the Argument from Potential in times of human embryo-like structures. MEDICINE, HEALTH CARE, AND PHILOSOPHY 2024; 27:37-48. [PMID: 37902931 PMCID: PMC10904491 DOI: 10.1007/s11019-023-10181-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 09/26/2023] [Indexed: 11/01/2023]
Abstract
Recent advancements in developmental biology enable the creation of embryo-like structures from human stem cells, which we refer to as human embryo-like structures (hELS). These structures provide promising tools to complement-and perhaps ultimately replace-the use of human embryos in clinical and fundamental research. But what if these hELS-when further improved-also have a claim to moral status? What would that imply for their research use? In this paper, we explore these questions in relation to the traditional answer as to why human embryos should be given greater protection than other (non-)human cells: the so-called Argument from Potential (AfP). According to the AfP, human embryos deserve special moral status because they have the unique potential to develop into persons. While some take the development of hELS to challenge the very foundations of the AfP, the ongoing debate suggests that its dismissal would be premature. Since the AfP is a spectrum of views with different moral implications, it does not need to imply that research with human embryos or hELS that (may) have 'active' potential should be completely off-limits. However, the problem with determining active potential in hELS is that this depends on development passing through 'potentiality switches' about the precise coordinates of which we are still in the dark. As long as this epistemic uncertainty persists, extending embryo research regulations to research with specific types of hELS would amount to a form of regulative precaution that as such would require further justification.
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Affiliation(s)
- Ana M Pereira Daoud
- Department of Health Ethics and Society, Maastricht University, Maastricht, The Netherlands.
- Department of Medical Humanities, University Medical Center Utrecht, Utrecht, The Netherlands.
- School for Oncology and Developmental Biology (GROW), Maastricht University, Maastricht, The Netherlands.
| | - Wybo J Dondorp
- Department of Health Ethics and Society, Maastricht University, Maastricht, The Netherlands
- School for Oncology and Developmental Biology (GROW), Maastricht University, Maastricht, The Netherlands
- School for Care and Public Health Research (CAPHRI), Maastricht University, Maastricht, The Netherlands
- Socrates chair Ethics of Reproductive Genetics endowed by the Dutch Humanist Association, Amsterdam, The Netherlands
| | | | - Guido M W R De Wert
- Department of Health Ethics and Society, Maastricht University, Maastricht, The Netherlands
- School for Oncology and Developmental Biology (GROW), Maastricht University, Maastricht, The Netherlands
- School for Care and Public Health Research (CAPHRI), Maastricht University, Maastricht, The Netherlands
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8
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Liu X, Polo JM. Human blastoid as an in vitro model of human blastocysts. Curr Opin Genet Dev 2024; 84:102135. [PMID: 38052115 DOI: 10.1016/j.gde.2023.102135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Revised: 10/23/2023] [Accepted: 11/03/2023] [Indexed: 12/07/2023]
Abstract
Human development is a highly coordinated process, with any abnormalities during the early embryonic stages that can often have detrimental consequences. The complexity and nuances of human development underpin its significance in embryo research. However, this research is often hindered by limited availability and ethical considerations associated with the use of donated blastocysts from in vitro fertilization (IVF) surplus. Human blastoids offer promising alternatives as they can be easily generated and manipulated in the laboratory while preserving key characteristics of human blastocysts. In this way, they hold the potential to serve as a scalable and ethically permissible resource in embryology research. By utilizing such human embryo models, we can establish a transformative platform that complements the study with IVF embryos, ultimately enhancing our understanding of human embryogenesis.
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Affiliation(s)
- Xiaodong Liu
- School of Life Sciences, Westlake University, Hangzhou, Zhejiang, China; Research Center for Industries of the Future, Westlake University, Hangzhou, China; Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang, China; Westlake Institute for Advanced Study, Hangzhou, Zhejiang, China.
| | - Jose M Polo
- Adelaide Centre for Epigenetics, School of Biomedicine, Faculty of Health and Medical Sciences, The University of Adelaide, South Australia, Australia; The South Australian Immunogenomics Cancer Institute, Faculty of Health and Medical Sciences, The University of Adelaide, South Australia, Australia; Department of Anatomy and Developmental Biology, Monash University, Victoria, Australia; Development and Stem Cells Program, Monash Biomedicine Discovery Institute, Victoria, Australia.
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9
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de Graeff N, De Proost L, Munsie M. 'Ceci n'est pas un embryon?' The ethics of human embryo model research. Nat Methods 2023; 20:1863-1867. [PMID: 38057511 PMCID: PMC7615661 DOI: 10.1038/s41592-023-02066-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/08/2023]
Abstract
Increasingly advanced in vitro stem-cell-derived human embryo models raise novel ethical questions and shed a light on long-standing questions regarding research on human embryos.
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Affiliation(s)
- Nienke de Graeff
- Department of Medical Ethics & Health Law, Leiden University Medical Center, Leiden University, Leiden, the Netherlands.
| | - Lien De Proost
- Department of Medical Ethics & Health Law, Leiden University Medical Center, Leiden University, Leiden, the Netherlands
- Developmental Biology, Erasmus Medical Center, Rotterdam, the Netherlands
| | - Megan Munsie
- Stem Cell Biology Theme, Murdoch Children's Research Institute, Melbourne, Victoria, Australia
- Department of Medicine, University of Melbourne, Melbourne, Victoria, Australia
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10
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Wang L, Zheng Y, Sun Y, Mao S, Li H, Bo X, Li C, Chen H. TimeTalk uses single-cell RNA-seq datasets to decipher cell-cell communication during early embryo development. Commun Biol 2023; 6:901. [PMID: 37660148 PMCID: PMC10475079 DOI: 10.1038/s42003-023-05283-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Accepted: 08/24/2023] [Indexed: 09/04/2023] Open
Abstract
Early embryonic development is a dynamic process that relies on proper cell-cell communication to form a correctly patterned embryo. Early embryo development-related ligand-receptor pairs (eLRs) have been shown to guide cell fate decisions and morphogenesis. However, the scope of eLRs and their influence on early embryo development remain elusive. Here, we developed a computational framework named TimeTalk from integrated public time-course mouse scRNA-seq datasets to decipher the secret of eLRs. Extensive validations and analyses were performed to ensure the involvement of identified eLRs in early embryo development. Process analysis identified that eLRs could be divided into six temporal windows corresponding to sequential events in the early embryo development process. With the interpolation strategy, TimeTalk is powerful in revealing paracrine settings and studying cell-cell communication during early embryo development. Furthermore, by using TimeTalk in the blastocyst and blastoid models, we found that the blastoid models share the core communication pathways with the epiblast and primitive endoderm lineages in the blastocysts. This result suggests that TimeTalk has transferability to other bio-dynamic processes. We also curated eLRs recognized by TimeTalk, which may provide valuable clues for understanding early embryo development and relevant disorders.
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Affiliation(s)
- Longteng Wang
- Peking University-Tsinghua University-National Institute of Biological Sciences Joint Graduate Program, School of Life Sciences, Peking University, Beijing, 100871, China
- Center for Bioinformatics, School of Life Sciences, Center for Statistical Science, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China
| | - Yang Zheng
- Institute of Health Service and Transfusion Medicine, Beijing, 100850, China
| | - Yu Sun
- Institute of Health Service and Transfusion Medicine, Beijing, 100850, China
| | - Shulin Mao
- Center for Bioinformatics, School of Life Sciences, Center for Statistical Science, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China
- Yuanpei College, Peking University, Beijing, 100871, China
| | - Hao Li
- Institute of Health Service and Transfusion Medicine, Beijing, 100850, China
| | - Xiaochen Bo
- Center for Bioinformatics, School of Life Sciences, Center for Statistical Science, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China
| | - Cheng Li
- Center for Bioinformatics, School of Life Sciences, Center for Statistical Science, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China.
| | - Hebing Chen
- Institute of Health Service and Transfusion Medicine, Beijing, 100850, China.
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11
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Rivron NC, Martinez Arias A, Pera MF, Moris N, M'hamdi HI. An ethical framework for human embryology with embryo models. Cell 2023; 186:3548-3557. [PMID: 37595564 DOI: 10.1016/j.cell.2023.07.028] [Citation(s) in RCA: 32] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2023] [Revised: 04/24/2023] [Accepted: 07/18/2023] [Indexed: 08/20/2023]
Abstract
A human embryo's legal definition and its entitlement to protection vary greatly worldwide. Recently, human pluripotent stem cells have been used to form in vitro models of early embryos that have challenged legal definitions and raised questions regarding their usage. In this light, we propose a refined legal definition of an embryo, suggest "tipping points" for when human embryo models could eventually be afforded similar protection to that of embryos, and then revisit basic ethical principles that might help to draft a roadmap for the gradual, justified usage of embryo models in a manner that aims to maximize benefits to society.
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Affiliation(s)
- Nicolas C Rivron
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna Biocenter (VBC), 1030 Vienna, Austria.
| | - Alfonso Martinez Arias
- Systems Bioengineering, DCEXS, Universidad Pompeu Fabra, Doctor Aiguader 88 ICREA (Institució Catalana de Recerca i Estudis Avançats), Barcelona, Spain
| | | | - Naomi Moris
- The Francis Crick Institute, 1 Midland Road, NW1 1AT London, UK
| | - Hafez Ismaili M'hamdi
- Department of Medical Ethics, Philosophy and History of Medicine, Erasmus MC, University Medical Centre, Rotterdam, the Netherlands
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12
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Zhang M, Reis AH, Simunovic M. Human embryoids: A new strategy of recreating the first steps of embryonic development in vitro. Semin Cell Dev Biol 2023; 141:14-22. [PMID: 35871155 DOI: 10.1016/j.semcdb.2022.07.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Revised: 06/05/2022] [Accepted: 07/04/2022] [Indexed: 01/24/2023]
Abstract
Molecular mechanisms surrounding early human embryonic events such as blastocyst formation, implantation, and the specification of the body axes are some of the most attractive research questions of developmental biology today. A knowledge on the detailed signaling landscape underlying these critical events in the human could impact the way we treat early pregnancy disorders and infertility, and considerably advance our abilities to make precise human tissues in a lab. However, owing to ethical, technical, and policy restrictions, research on early human embryo development historically stalled behind animal models. The rapid progress in 3D culture of human embryonic stem cells over the past years created an opportunity to overcome this critical challenge. We review recently developed strategies of making 3D models of the human embryo built from embryonic stem cells, which we refer to as embryoids. We focus on models aimed at reconstituting the 3D epithelial characteristics of the early human embryo, namely the intra/extraembryonic signaling crosstalk, tissue polarity, and embryonic cavities. We identify distinct classes of embryoids based on whether they explicitly include extraembryonic tissues and we argue for the merit of compromising on certain aspects of embryo mimicry in balancing the experimental feasibility with ethical considerations. Human embryoids open gates toward a new field of synthetic human embryology, allowing to study the long inaccessible stages of early human development at unprecedented detail.
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Affiliation(s)
- Miaoci Zhang
- Department of Chemical Engineering, Fu Foundation School of Engineering and Applied Sciences, Columbia University, New York 10027, USA; Columbia Stem Cell Initiative, Columbia University Irving Medical Center, New York 10032, USA
| | - Alice H Reis
- Department of Chemical Engineering, Fu Foundation School of Engineering and Applied Sciences, Columbia University, New York 10027, USA; Columbia Stem Cell Initiative, Columbia University Irving Medical Center, New York 10032, USA
| | - Mijo Simunovic
- Department of Chemical Engineering, Fu Foundation School of Engineering and Applied Sciences, Columbia University, New York 10027, USA; Columbia Stem Cell Initiative, Columbia University Irving Medical Center, New York 10032, USA; Department of Genetics and Development, Columbia Irving Medical Center, New York 10032, USA.
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13
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Heidari Khoei H, Javali A, Kagawa H, Sommer TM, Sestini G, David L, Slovakova J, Novatchkova M, Scholte Op Reimer Y, Rivron N. Generating human blastoids modeling blastocyst-stage embryos and implantation. Nat Protoc 2023; 18:1584-1620. [PMID: 36792779 DOI: 10.1038/s41596-023-00802-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Accepted: 12/08/2022] [Indexed: 02/17/2023]
Abstract
Human early development sets the stage for embryonic and adult life but remains difficult to investigate. A solution came from the ability of stem cells to organize into structures resembling preimplantation embryos-blastocysts-that we termed blastoids. This embryo model is available in unlimited numbers and could thus support scientific and medical advances. However, its predictive power depends on how faithfully it recapitulates the blastocyst. Here, we describe how we formed human blastoids that (1) efficiently achieve the morphology of the blastocyst and (2) form lineages according to the pace and sequence of blastocyst development, (3) ultimately forming cells that transcriptionally reflect the blastocyst (preimplantation stage). We employ three different commercially available 96- and 24-well microwell plates with results similar to our custom-made ones, and show that blastoids form in clinical in vitro fertilization medium and can be cryopreserved for shipping. Finally, we explain how blastoids replicate the directional process of implantation into endometrial organoids, specifically when these are hormonally stimulated. It takes 4 d for human blastoids to form and 10 d to prepare the endometrial implantation assay, and we have cultured blastoids up to 6 d (time-equivalent of day 13). On the basis of our experience, we anticipate that a person with ~1 year of human pluripotent stem cell culture experience and of organoid culture should be able to perform the protocol. Altogether, blastoids offer an opportunity to establish scientific and biomedical discovery programs for early pregnancy, and an ethical alternative to the use of embryos.
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Affiliation(s)
- Heidar Heidari Khoei
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Vienna, Austria
| | - Alok Javali
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Vienna, Austria
| | - Harunobu Kagawa
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Vienna, Austria
| | - Theresa Maria Sommer
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Vienna, Austria
| | - Giovanni Sestini
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Vienna, Austria
| | - Laurent David
- Université de Nantes, CHU Nantes, Inserm, CR2TI, UMR 1064, Nantes, France.,Université de Nantes, CHU Nantes, Inserm, CNRS, BioCore, Nantes, France
| | - Jana Slovakova
- Institute of Molecular Biotechnology of the Austrian Academy of Science (IMBA), IMBA Stem Cell Core Facility (ISCCF), Vienna BioCenter (VBC), Vienna, Austria
| | - Maria Novatchkova
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Vienna, Austria.,Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Vienna, Austria
| | - Yvonne Scholte Op Reimer
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Vienna, Austria
| | - Nicolas Rivron
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Vienna, Austria.
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14
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Wang X, Hu G. Human embryos in a dish – modeling early embryonic development with pluripotent stem cells. CELL REGENERATION 2022; 11:4. [PMID: 35029775 PMCID: PMC8760366 DOI: 10.1186/s13619-022-00107-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Accepted: 01/06/2022] [Indexed: 11/10/2022]
Abstract
Stem cell-based embryo models present new opportunities to study early embryonic development. In a recent study, Kagawa et al. identified an approach to create human pluripotent stem cell-based blastoids that resemble the human blastocysts. These blastoids efficiently generated analogs of the EPI, TE, PrE lineages with transcriptomes highly similar to those found in vivo. Furthermore, the formation of these lineages followed the same sequence and pace of blastocyst development, and was also dependent on the same pathways required for lineage specification. Finally, the blastoids were capable of attaching to stimulated endometrial cells to mimic the process of implantation. While more comprehensive analysis is needed to confirm its validity and usefulness, this new blastoid system presents the latest development in the attempt to model early human embryogenesis in vitro.
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15
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Malik V, Zang R, Fuentes-Iglesias A, Huang X, Li D, Fidalgo M, Zhou H, Wang J. Comparative functional genomics identifies unique molecular features of EPSCs. Life Sci Alliance 2022; 5:5/11/e202201608. [PMID: 35961778 PMCID: PMC9378845 DOI: 10.26508/lsa.202201608] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Revised: 07/19/2022] [Accepted: 07/20/2022] [Indexed: 12/03/2022] Open
Abstract
The authors provide a comprehensive resource on proteomics, transcriptomic, and epigenetic level details of EPSCs to shed light on possible molecular pathways regulating their expanded pluripotency potential. Extended pluripotent or expanded potential stem cells (EPSCs) possess superior developmental potential to embryonic stem cells (ESCs). However, the molecular underpinning of EPSC maintenance in vitro is not well defined. We comparatively studied transcriptome, chromatin accessibility, active histone modification marks, and relative proteomes of ESCs and the two well-established EPSC lines to probe the molecular foundation underlying EPSC developmental potential. Despite some overlapping transcriptomic and chromatin accessibility features, we defined sets of molecular signatures that distinguish EPSCs from ESCs in transcriptional and translational regulation as well as metabolic control. Interestingly, EPSCs show similar reliance on pluripotency factors Oct4, Sox2, and Nanog for self-renewal as ESCs. Our study provides a rich resource for dissecting the regulatory network that governs the developmental potency of EPSCs and exploring alternative strategies to capture totipotent stem cells in culture.
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Affiliation(s)
- Vikas Malik
- Department of Medicine, Columbia Center for Human Development, Columbia Stem Cell Initiative, Herbert Irving Comprehensive Cancer Center, Columbia University Irving Medical Center, New York, NY, USA
| | - Ruge Zang
- Department of Medicine, Columbia Center for Human Development, Columbia Stem Cell Initiative, Herbert Irving Comprehensive Cancer Center, Columbia University Irving Medical Center, New York, NY, USA
| | - Alejandro Fuentes-Iglesias
- Department of Physiology, Center for Research in Molecular Medicine and Chronic Diseases (CiMUS), Universidade de Santiago de Compostela (USC)-Health Research Institute (IDIS), Santiago de Compostela, Spain
| | - Xin Huang
- Department of Medicine, Columbia Center for Human Development, Columbia Stem Cell Initiative, Herbert Irving Comprehensive Cancer Center, Columbia University Irving Medical Center, New York, NY, USA
| | - Dan Li
- Department of Medicine, Columbia Center for Human Development, Columbia Stem Cell Initiative, Herbert Irving Comprehensive Cancer Center, Columbia University Irving Medical Center, New York, NY, USA
| | - Miguel Fidalgo
- Department of Physiology, Center for Research in Molecular Medicine and Chronic Diseases (CiMUS), Universidade de Santiago de Compostela (USC)-Health Research Institute (IDIS), Santiago de Compostela, Spain
| | - Hongwei Zhou
- Department of Medicine, Columbia Center for Human Development, Columbia Stem Cell Initiative, Herbert Irving Comprehensive Cancer Center, Columbia University Irving Medical Center, New York, NY, USA
| | - Jianlong Wang
- Department of Medicine, Columbia Center for Human Development, Columbia Stem Cell Initiative, Herbert Irving Comprehensive Cancer Center, Columbia University Irving Medical Center, New York, NY, USA
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16
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Sozen B, Conkar D, Veenvliet JV. Carnegie in 4D? Stem-cell-based models of human embryo development. Semin Cell Dev Biol 2022; 131:44-57. [PMID: 35701286 DOI: 10.1016/j.semcdb.2022.05.023] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Revised: 05/23/2022] [Accepted: 05/24/2022] [Indexed: 12/14/2022]
Abstract
How cells build embryos is still a major mystery. Many unresolved questions require the study of the processes that pattern and shape the embryo in live specimens, in toto, across spatial and temporal scales. In mammalian embryogenesis, this remains a major challenge as the embryo develops in utero, precluding easy accessibility. For human embryos, technical, ethical and legal limitations further hamper the in-depth investigation of embryogenesis, especially beyond gastrulation stages. This has resulted in an over-reliance on model organisms, particularly mice, to understand mammalian development. However, recent efforts show critical differences between rodent and primate embryos, including timing, architecture and transcriptional regulation. Thus, a human-centric understanding of embryogenesis is much needed. To empower this, novel in vitro approaches, which coax human pluripotent stem cells to form embryonic organoids that model embryo development, are pivotal. Here, we summarize these emergent technologies that recapitulate aspects of human development "in a dish". We show how these technologies can provide insights into the molecular, cellular and morphogenetic processes that fuel the formation of a fully formed fetus, and discuss the potential of these platforms to revolutionize our understanding of human development in health and disease. Despite their clear promise, we caution against over-interpreting the extent to which these in vitro platforms model the natural embryo. In particular, we discuss how fate, form and function - a tightly coupled trinity in vivo, can be disconnected in vitro. Finally, we propose how careful benchmarking of existing models, in combination with rational protocol design based on an increased understanding of in vivo developmental dynamics and insights from mouse in vitro models of embryo development, will help guide the establishment of better models of human embryo development.
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Affiliation(s)
- Berna Sozen
- Department of Genetics, Yale School of Medicine, Yale University, New Haven, CT, 06510, USA; Yale Stem Cell Center, Yale University, New Haven, CT 06520, USA.
| | - Deniz Conkar
- Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108, 01307 Dresden, Germany
| | - Jesse V Veenvliet
- Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108, 01307 Dresden, Germany; Cluster of Excellence Physics of Life, Technische Universität Dresden, 01307 Dresden, Germany.
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17
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Abstract
The complex process by which a single-celled zygote develops into a viable embryo is nothing short of a miraculous wonder of the natural world. Elucidating how this process is orchestrated in humans has long eluded the grasp of scientists due to ethical and practical limitations. Thankfully, pluripotent stem cells that resemble early developmental cell types possess the ability to mimic specific embryonic events. As such, murine and human stem cells have been leveraged by scientists to create in vitro models that aim to recapitulate different stages of early mammalian development. Here, we examine the wide variety of stem cell-based embryo models that have been developed to recapitulate and study embryonic events, from pre-implantation development through to early organogenesis. We discuss the applications of these models, key considerations regarding their importance within the field, and how such models are expected to grow and evolve to achieve exciting new milestones in the future.
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Affiliation(s)
- Aidan H. Terhune
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI 48109, USA
| | - Jeyoon Bok
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI 48109, USA
| | - Shiyu Sun
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI 48109, USA
| | - Jianping Fu
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI 48109, USA
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109, USA
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
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18
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Ghazimoradi MH, Khalafizadeh A, Babashah S. A critical review on induced totipotent stem cells: Types and methods. Stem Cell Res 2022; 63:102857. [PMID: 35872523 DOI: 10.1016/j.scr.2022.102857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/23/2022] [Revised: 06/22/2022] [Accepted: 07/05/2022] [Indexed: 11/25/2022] Open
Abstract
Totipotent stem cells are cells with the capacity to form an entire embryo. Many attempts have been made to convert other types of cells to totipotent stem cells which we called induced totipotent stem cells. Various aspects of these cells such as transcriptional and epigenetics networks are unique. By taking advantage of these aspects, efficient methods have been provided to induce totipotent stem cells. Although this advancement is significant, many aspects of induction such as the underlying mechanism remain to be elucidated. On the other hand, embryonic stem cells usually are the source of induction which raise important questions regarding if these methods are induction or promotion of 2C intrinsic totipotent cells in ESC culture. Here, we review the latest mouse progress in underling mechanism of induction of totipotent stem cells. In addition, we follow up on the progress of Blastoids derived from totipotent stem cells.
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Affiliation(s)
- Mohammad H Ghazimoradi
- Department of Molecular Genetics, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran
| | - Ali Khalafizadeh
- Department of Molecular Genetics, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran
| | - Sadegh Babashah
- Department of Molecular Genetics, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran.
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19
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Malaguti M, Portero Migueles R, Annoh J, Sadurska D, Blin G, Lowell S. SyNPL: Synthetic Notch pluripotent cell lines to monitor and manipulate cell interactions in vitro and in vivo. Development 2022; 149:275525. [PMID: 35616331 PMCID: PMC9270970 DOI: 10.1242/dev.200226] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Accepted: 05/13/2022] [Indexed: 12/11/2022]
Abstract
Cell-cell interactions govern differentiation and cell competition in pluripotent cells during early development, but the investigation of such processes is hindered by a lack of efficient analysis tools. Here, we introduce SyNPL: clonal pluripotent stem cell lines that employ optimised Synthetic Notch (SynNotch) technology to report cell-cell interactions between engineered ‘sender’ and ‘receiver’ cells in cultured pluripotent cells and chimaeric mouse embryos. A modular design makes it straightforward to adapt the system for programming differentiation decisions non-cell-autonomously in receiver cells in response to direct contact with sender cells. We demonstrate the utility of this system by enforcing neuronal differentiation at the boundary between two cell populations. In summary, we provide a new adaptation of SynNotch technology that could be used to identify cell interactions and to profile changes in gene or protein expression that result from direct cell-cell contact with defined cell populations in culture and in early embryos, and that can be customised to generate synthetic patterning of cell fate decisions. Summary: Optimised Synthetic Notch circuitry in mouse pluripotent stem cells provides a modular tool with which to monitor cell-cell interactions and program synthetic patterning of cell fates in culture and in embryos.
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Affiliation(s)
- Mattias Malaguti
- Centre for Regenerative Medicine, Institute for Stem Cell Research, School of Biological Sciences, University of Edinburgh, 5 Little France Drive, Edinburgh EH16 4UU, UK
| | - Rosa Portero Migueles
- Centre for Regenerative Medicine, Institute for Stem Cell Research, School of Biological Sciences, University of Edinburgh, 5 Little France Drive, Edinburgh EH16 4UU, UK
| | - Jennifer Annoh
- Centre for Regenerative Medicine, Institute for Stem Cell Research, School of Biological Sciences, University of Edinburgh, 5 Little France Drive, Edinburgh EH16 4UU, UK
| | - Daina Sadurska
- Centre for Regenerative Medicine, Institute for Stem Cell Research, School of Biological Sciences, University of Edinburgh, 5 Little France Drive, Edinburgh EH16 4UU, UK
| | - Guillaume Blin
- Centre for Regenerative Medicine, Institute for Stem Cell Research, School of Biological Sciences, University of Edinburgh, 5 Little France Drive, Edinburgh EH16 4UU, UK
| | - Sally Lowell
- Centre for Regenerative Medicine, Institute for Stem Cell Research, School of Biological Sciences, University of Edinburgh, 5 Little France Drive, Edinburgh EH16 4UU, UK
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20
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Needham J, Metzis V. Heads or tails: Making the spinal cord. Dev Biol 2022; 485:80-92. [DOI: 10.1016/j.ydbio.2022.03.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 12/15/2021] [Accepted: 03/02/2022] [Indexed: 12/14/2022]
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21
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Rossant J, Tam PP. Early human embryonic development: Blastocyst formation to gastrulation. Dev Cell 2022; 57:152-165. [DOI: 10.1016/j.devcel.2021.12.022] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2021] [Revised: 11/29/2021] [Accepted: 12/22/2021] [Indexed: 12/13/2022]
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22
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OUP accepted manuscript. Mol Hum Reprod 2022; 28:6551255. [DOI: 10.1093/molehr/gaac008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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23
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Ramakrishna NB, Murison K, Miska EA, Leitch HG. Epigenetic Regulation during Primordial Germ Cell Development and Differentiation. Sex Dev 2021; 15:411-431. [PMID: 34847550 DOI: 10.1159/000520412] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Accepted: 10/10/2021] [Indexed: 11/19/2022] Open
Abstract
Germline development varies significantly across metazoans. However, mammalian primordial germ cell (PGC) development has key conserved landmarks, including a critical period of epigenetic reprogramming that precedes sex-specific differentiation and gametogenesis. Epigenetic alterations in the germline are of unique importance due to their potential to impact the next generation. Therefore, regulation of, and by, the non-coding genome is of utmost importance during these epigenomic events. Here, we detail the key chromatin changes that occur during mammalian PGC development and how these interact with the expression of non-coding RNAs alongside broader epitranscriptomic changes. We identify gaps in our current knowledge, in particular regarding epigenetic regulation in the human germline, and we highlight important areas of future research.
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Affiliation(s)
- Navin B Ramakrishna
- Wellcome/CRUK Gurdon Institute, University of Cambridge, Cambridge, United Kingdom
- Department of Genetics, University of Cambridge, Cambridge, United Kingdom
- Genome Institute of Singapore, A*STAR, Biopolis, Singapore, Singapore
| | - Keir Murison
- MRC London Institute of Medical Sciences, London, United Kingdom
- Institute of Clinical Sciences, Imperial College London, London, United Kingdom
| | - Eric A Miska
- Wellcome/CRUK Gurdon Institute, University of Cambridge, Cambridge, United Kingdom
- Department of Genetics, University of Cambridge, Cambridge, United Kingdom
- Wellcome Sanger Institute, Wellcome Trust Genome Campus, Cambridge, United Kingdom
| | - Harry G Leitch
- MRC London Institute of Medical Sciences, London, United Kingdom
- Institute of Clinical Sciences, Imperial College London, London, United Kingdom
- Centre for Paediatrics and Child Health, Faculty of Medicine, Imperial College London, London, United Kingdom
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24
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The closer the knit, the tighter the fit: conceptual and ethical issues of human embryo modelling. Reprod Biomed Online 2021; 43:1123-1125. [PMID: 34706836 DOI: 10.1016/j.rbmo.2021.08.031] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 08/08/2021] [Accepted: 08/16/2021] [Indexed: 11/21/2022]
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25
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Denker HW. Autonomy in the Development of Stem Cell-Derived Embryoids: Sprouting Blastocyst-Like Cysts, and Ethical Implications. Cells 2021; 10:1461. [PMID: 34200796 PMCID: PMC8230544 DOI: 10.3390/cells10061461] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2021] [Revised: 05/23/2021] [Accepted: 06/04/2021] [Indexed: 12/19/2022] Open
Abstract
The experimental production of complex structures resembling mammalian embryos (e.g., blastoids, gastruloids) from pluripotent stem cells in vitro has become a booming research field. Since some of these embryoid models appear to reach a degree of complexity that may come close to viability, a broad discussion has set in with the aim to arrive at a consensus on the ethical implications with regard to acceptability of the use of this technology with human cells. The present text focuses on aspects of the gain of organismic wholeness of such stem cell-derived constructs, and of autonomy of self-organization, raised by recent reports on blastocyst-like cysts spontaneously budding in mouse stem cell cultures, and by previous reports on likewise spontaneous formation of gastrulating embryonic disc-like structures in primate models. Mechanisms of pattern (axis) formation in early embryogenesis are discussed in the context of self-organization of stem cell clusters. It is concluded that ethical aspects of development of organismic wholeness in the formation of embryoids need to receive more attention in the present discussions about new legal regulations in this field.
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Affiliation(s)
- Hans-Werner Denker
- Universitätsklinikum, Institut für Anatomie, University Duisburg-Essen, Hufelandstr. 55, 45147 Essen, Germany
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